Liquid gauge and system



8' 1935. E. HUBBARD LIQUID GAUGE AND SYSTEM Filed Jan. 21, 1930 FZG. 1.

FZG.2.

R0 WW 2 m mm. w o IA L E w a m, 8 I EY w w A? 4 5 Pr /A]HIH/ 7 X o z ww w R f? M) w UNITED STATES PATENT OFFICE 2,012,511 LIQUID GAUGE AND SYSTEM Edward L. Hubbard, Piedmont, Water Works Supply Calif., assignor Company, San

Francisco, Calif., a corporation of California Application January 21, 1930, Serial No. 422,241

d Claims. (01. 73-54! This invention relates to liquidfldepth gauges of the manometer type and has for its 0131601751111 provements in such apparatus forigauging the depths of liquids.

In the drawing annex d hereto vation partly in section showing Fig. l is an eley au e ap paratus connected to, an underground tankand indicating the depth of its contained liquid.

Fig.2 is an enlarged sectionalview of the special pump valve construction used in the apparatus.

In further detail the drawing tank! of any size and containing 3 shows a buried ay a total depth of liquid 2 or six feet three inches asindicated.

The tank has a vented filling plug at 3 and is connected to the gauge proper by a small tube 4 which connects to the upper end of a vertical pipe 5 carrying at its lower or cylinder 6 cut off at an angle end an enlarged chamber at 1 so that its point touches the bottom of the tank and the upper end of the angular cut is about two or three inches above Fig. 1. v

The gauge comprises a framea the bottom as indicated at R in provided at its lower end with a chamber 9 preferably made of brass and which cha ber has two risers l0 and H cross connected near their upper ends by a transverse passageway [2,

while between the risers and to the rear of the passageway 12 is a vertical glass reading tube 13 passing air tight into the chamber and terminating at its l4 near the bottom through a stuffing box 3| lower end within the liquid of the chamber 9, and at its upper flow chamber l5 Stufiing box 31 is preferably packed vented to atmosphere.

end in an overwith cork and it should be noted that it ispositioned below the level of the gauging liquid l4 seal liquid only.

Tube 4 from to the upper end upper end of riser l l is an air the tank connects so that it need air tight at 16 of riser Ill, and fitted into the pump for pumping air into the system for forcing all liquid down and out of pipe 5 and chamber 6 to the three-inch line or highest part (X) of the slanted opening in chamber 6.

The pump comprises a or screwed air tight into brass cylinder l1 sealed the upper end of riser H and is fitted inside with a plunger 18 having a packer The packer it contracts sufficiently on the air to leak downward around on the down stroke it is pressure and inner walls of the cylinder 11, at of the well known bicycle pump.

19 and an operating pump handle 20.

I9 functions as an intake up stroke to permit the plunger 18, and expanded by the back forms an air-tight seal against the valve, since ter the manner The lower head trapping air, all as best shown in 21' tothe liquid 14 so shown are used to gauge liquids such as water, gasoline, fuel oil, alcohol,

2| of the cylinder is pierced by a small central hole 22 about a sixteenth of an inch in diameter surrounded on its lower end by a short nipple forming ,a valve seat 23 against which seats a cork. 24 held in a vertically reciprocable cage 25 pressed upward by a spring 26 andvented against Fig. 2. 21 isported at its lower end that the cage 25 can move up and down freely, and is also ported just under 510 the head H as indicated at 28 to permit the escape of theair forced down by the pump.

Ports 28 are at such an elevation and guarded oi the chamber 9 in such a manner that the air cannot find its way across the chamber 9 to bubble up under riser 10, but must ascend riser I I and then pass over through lateral passage The valve housing 121to riser l0, thus overcoming any tendency to violently carry liquid spray over into tube 4 or af- With an arrangement of the kind so far described it is manifest that upon pumping a pressure of air into the system to displace all liquid from pipe 5 the pressure will have to balance the 25 weight of liquid above point X in the tank and hence will also balance a liquid gauge column 29 of equal height ifthevgauge liquid is of equal specific gravity, or of lesser height if the gauge liquid I4 is heavier, it being the ordinary practice 30 in gauges of this kind to use a gauging liquid much heavier than the liquid to be gauged, so that the reading column will be kept short.

Therefore, since gauges of the type herein the depth of various lubricating oil of various weights, and many other liquids, it follows that if any particular liquid were chosen for the gauging liquid it would have a difierent specific gravity relation to each 40 different liquid to be gauged and would therefore require a special graduation of the depth scale 30 for each liquid to which it was applied, also for gauging very heavy liquids, say sulfuric acid, the instrument would have to be several times as long as for gauging gasoline. Thus, for every installation it would be necessary to ascertain the specific gravity of the liquid to be gauged, compute its relation to the specific gravity of the gauge column liquid and engrave the scale especially to suit. In lieu of this, a large line of instruments must be carried.

In an attempt to overcome the difficulty mentioned and be able to meet any gauging requirement with one size of instrument with a single which are perfectly miscible .ratus has a uniform scale I discovered that if the gauging liquid M is compounded of two or more dissimilar weight liquids, say a heavy one and a light one that are perfectly miscible, that the proper relation of a single scale to any liquid to be gauged and since their specific gravities are respectively about 2.9823 and .8816 it will be seen that a scale of substantially 3 to 1 may be maintained over a wide range (using the acetyl-tetra-bromide pure in gauging water) or if a longer reading scale is desired I may mix suitable quantities to make a 2 or 2 to 1 weight ratio, but w 'chever ratio is adopted will handle all liquids within a reasonable range with but the one reading scale.

Instead of the above liquids I may use a mixture of ethylene (specific gravity 2.16) with a non-volatile mineral oil of any chosen weight for a diluent, or any two dissimilar weight liquids as are the above such as alcohol and bromoform, or I may vary the weight of a given liquid such as water by dissolving various amounts of a heavy metallic salt such as silver nitrate .therein. The principal feature of importance being to vary the weight of the gauging liquid to compensate for the particular weight of the liquid to be gauged so as to read correctly on a fixed scale drawn to some arbitrary relation to give a desired length of reading column.

The construction of the pump valve of cork I have found necessary in using the first mixture above described as other pliable substances useful for valves are speedily ruined by the liquid and hence the specific construction of the apparelation to the specific liquids used.

In practice pipe 5 is kept a short distance above the bottom of the tank to be gauged'to allow for sludge or foreign matter which may settle in the liquid. This lower stratum or residue is termed R in the drawing and on the gauge colunm and its depth is determined by the angular cutting off of cylinder 6 which establishes the point X or effective lower end of pipe 5. Cylinder 6 being large takes care of the eiTect of heat and cold on tube 4 since the bore of this tube is very small and its capacity relative to capacity of cylinder 6 is therefore negligible.

Having thus described my invention and the manner of its use, I claim:

1. In a pressure gauge, a gauge column, a chamber for the gauge column liquid at the base of the column and communicating near its bottom with the column, a pair of risers on said chamber, and a cross duct connecting the risers I above the level of the gauging liquid, one of said risers being provided with a pressure pipe connection from the liquid to be gauged, and the other with means for introducing a gas under pressure.

2. In a pressure gauge, a gauge column, a chamber for the gauge column liquid at the base of the column and communicating near its bottom with the column, a pair of risers on said chamber, and a cross duct connecting the risers above the level of the gauging liquid, one of said risers provided with a pressure pipe connection from the liquid to be gauged, and a cylindrical air pump extending within the other said riser and discharging below the surface of the liquid level therein.

3. A device for indicating the level of liquid in a tank, which comprises, a tube of transparent material, there being a measuring scale adjacent the tube, a chamber containing gauging liquid connected to the bottom of the tube, two nipples on the top of'said chamber, a duct interconnecting said nipples above the level of the gauging liquid, an air pump mounted in one of saidnipples and having its discharge end pr0- jecting into the gauging liquid in said chamber, and a tube in communication with the liquid adjacent the bottom of the tank and connected to the other of said nipples.

4. A device for indicating the level of liquid in a tank, which comprises,-a tube of transparent material, there being a measuring scale adjacent the tube, a chamber containing gauging liquid connected to the bottom of the tube, two nipples on the top of said chamber, a duct interconnecting said nipples above the level of the gauging liquid, an air pump mounted in one of said nipples and having its discharge end projecting into the gauging liquid in said chamber, a tube in communication with the liquid adjacent the bottom of the tank and connected to the other of said nipples, andan open chamber on the upper end of and communicating with the tube for receiving the overflow liquid from the tube.

EDWARD L. HUBBARD." 

